When developing an underground mine, an array of tunnels and corridors have to be made through the rock and soil to reach the ore; these include vertical shafts, inclined tunnels, and horizontal tunnels. In most cases, the mine tunnels or raises have to be blasted through the rock or mineral, with explosive charges. These explosive charges will be installed at the end portion of a hole that is drilled through the rock, to obtain the desired effect.
Explosive charges are also used to extract ore from the integral rock formation. Again, the explosive charges are installed inside a hole that has been drilled into the rock to extract ore from the rock fragments.
Also, metallic cables are installed in the mine corridors, to retain the mine walls and thus help to provide an increased structural integrity of the mine walls. These retaining cables, which may be submitted to important forces and stresses, are installed on the outer free extremity of elongated metallic rods which extend into the rock walls in holes pre-drilled therein.
In all these cases, holes have to be drilled through the solid rock formation in which the mine corridors are made. To drill such holes, drilling buggies equipped with a drilling tool arm used. Known drilling tools include pneumatic or hydraulic drilling tools of known construction.